Abstract
Reduction division and haploid chromosome number of several species and varieties of Triticum were studied in haematoxylin-stained microtome sections (16- 18 μ) after Bouin Allen fixation. Five stages of nuclear contraction ('ball') could usually be distinguished: preleptotene, prezygotene, postzygotene, postdiakinesis, postinterkinesis. Pachytene was not clear. A multipolar spindle frequently preceded the normal bipolar one in first prometaphase.
T. monococcum and T. dicoccoides (one variety each) had 7 chromosomes; T. dicoccum, T. turgidum, T. durum, T. polonicum (one variety each) 14; T. vulgare (eight varieties), T. compactum (two varieties), T. spella (one variety) 21. These observations confirm those of Sakamura and of Sax except for T. dicoccoides where Sax found n = 14. The frequent reports of n = 8 must be rejected. Taxonomic classifications from chromosome number agree with those from morphology, sexual affinity, serological and Vavilov methods, except for T. dicoccoides.
Relations between species, and origin were discussed on basis of published information and the present results. Hybridization (e.g. with Aegilops) was considered improbable because of hybrid sterility, but polyploidy must have been an important factor.
T. monococcum and T. dicoccoides (one variety each) had 7 chromosomes; T. dicoccum, T. turgidum, T. durum, T. polonicum (one variety each) 14; T. vulgare (eight varieties), T. compactum (two varieties), T. spella (one variety) 21. These observations confirm those of Sakamura and of Sax except for T. dicoccoides where Sax found n = 14. The frequent reports of n = 8 must be rejected. Taxonomic classifications from chromosome number agree with those from morphology, sexual affinity, serological and Vavilov methods, except for T. dicoccoides.
Relations between species, and origin were discussed on basis of published information and the present results. Hybridization (e.g. with Aegilops) was considered improbable because of hybrid sterility, but polyploidy must have been an important factor.
Original language | Dutch |
---|---|
Qualification | Doctor of Philosophy |
Awarding Institution | |
Supervisors/Advisors |
|
Award date | 27 Jun 1924 |
Place of Publication | 's-Gravenhage |
Publisher | |
DOIs | |
Publication status | Published - 27 Jun 1924 |
Keywords
- triticum aestivum
- wheat
- genetics
- cell division
- meiosis